1. Field of the Invention
The present invention relates to individual identification and tracking systems and, more particularly, to a system and method for identifying and tracking persons using RFID (Radio Frequency Identification) tagged items carried on the persons.
2. Description of the Related Art
Manufacturers, distributers and/or retailers have a need to track their products. Conventionally, a manufacturer, a distributor or a retailer attaches a Radio Frequency Identification (RFID) tag on each product to identify and track their merchandise. By the transmission and reception of radio signals to and from the RFID tag on the product, the product can be tracked from the time of manufacture to the time of sale without any direct visual or physical contact with the product being monitored. RFID tag information typically stored in a RFID tag of a product includes (1) a retail SKU number (e.g., UPC—universal product code) identifying the name, manufacturer and/or suggested price of the product, (2) a unique serial number identifying the product, or (3) the SKU number and the unique serial number. In the past, the SKU numbers have been printed on products in the form of bar codes which can be read by a Point-of-Sale (POS) terminal having a bar code scanner. A typical use of the SKU number is to look up the product price at the time of purchase. Merchants also use the SKU numbers to keep track of inventory so that they know which products are selling well and when to reorder the products from wholesalers. The unique serial number stored in a RFID tag can be a globally unique number or a number assigned in series to products manufactured in the same product category.
A typical RFID tag on a product includes an antenna and a silicon chip containing modulation circuits, control logic and non-volatile memory. The silicon chip derives electrical power from radio signals received by the antenna or from a battery, and is able to exchange data with a RFID tag scanner by demodulating and modulating the radio signals. The non-volatile memory of the RFID tag typically has a storage capacity of 5 to 256 bytes. A computer coupled to the RFID tag scanner can read and write to and from the memory of the RFID tag using radio signal transmission. A detailed description of the structure and operation of a RFID tag for a product is discussed in a co-pending application, U.S. application Ser. No. 09/790,104, filed on Feb. 21, 2001, owned by the assignee of the present application, and entitled “Method to Address Security and Privacy Issues of the Use of RFID Systems to Track Consumer Products”, which is herein fully incorporated by reference.
Due to the recent development of RFID tag technology, RFID tags can be manufactured inexpensively and in non-conspicuous miniature sizes, so that they can be integrated into products during the manufacturing process of the products, rather than being attached to the packaging of the products.